A CD burned to the ISO9660 standard can be read on a PC.
Mac OS X burns CDs in the ISO9660 standard by default.
So YES.
A CD burned on a Mac can be read on a PC.
I only know that I burn CDs on my Mac and read them on my PC all the time. But it does seem that the majority of people say that's impossible so maybe I am deluded. As always the best thing is to look at some independent evidence from expert reference sources.
Here are some references to support what I have said.
ISO 9660
An ISO 9660 file system is a standard CD-ROM file system that allows you to read the same CD-ROM whether you're on a PC, Mac, or other major computer platform. The standard, issued in 1988, was written by an industry group named High Sierra. Almost all computers with CD-ROM drives can read files from an ISO 9660 file system.
http://whatis.techtarget.com/definition/0,,sid9_gci212402,00.html
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In addition to burning simple CD-Rs and CD-RWs, both operating systems support writing to DVD-R, DVD-RW, and DVD+RW. Both can burn the cross-platform compatible ISO-9660 format, though only Mac OS X writes to that format by default. Windows XP also supports HighMAT format.
http://www.xvsxp.com/files/burning_advanced.php
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ISO 9660, a standard published by the International Organization for Standardization (ISO), defines a file system for CD-ROM media. It aims at supporting different computer operating systems such as Microsoft Windows, Mac OS, and systems that follow the Unix specification, so that data may be exchanged.
An extension to ISO 9660, the Joliet format, adds support to allow longer file names and non-ASCII character sets.
DVDs may also use the ISO 9660 file system. However, the UDF file system is more appropriate on DVDs as it has better support for the larger media and is better suited for modern operating system needs.
http://en.wikipedia.org/wiki/ISO_9660
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The Finder can burn files to a CD or DVD. You can then use that disc as a backup, send it to friends, or copy those files to another machine. Mac OS X burns discs that can also be used on Windows computers and other types of computers. Thie disc uses a HFS Plus/ISO 9660 hybrid format with these file systems: HFS+, ISO-9660 with Rock Ridge, and Joliet with Rock Ridge.
If your computer has a Combo drive, you can burn files onto CDs. If your computer has a SuperDrive, you can burn files on CDs and DVDs.
After you drag items to the disc, the Finder places aliases to them in the disc's window. When you burn the disc, the original files that the aliases point to are burned to the disc. In addition, if any folder in the burn folder contains aliases, the original files for those aliases are burned to the disc as well.
http://docs.info.apple.com/article.html?path=Mac/10.4/en/mh854.html
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